There’s no law or guidelines on the use of the term “aromatherapy” so any manufacturer, even those that include synthetic ingredients in their candles, can slap the word “aromatherapy” onto their label.
Holistic aromatherapy focuses and emphasizes the use of all natural ingredients whenever possible. Most candles are not all natural, even if they are marketed with the word aromatherapy. Burn candles made with synthetic ingredients (or even natural ingredients with toxic compounds), and despite how pleasantly fragrant the air is that you breathe, you will still inhale toxins.
Candles suitable for use in true aromatherapy are available, but they are hard to find and are generally costly.
The Choice of Wax Used to Produce the Candles
Candles made with waxes that emit toxins when burned (i.e. paraffin) aren’t suitable for aromatherapy. Holistic aromatherapy promotes use of all natural ingredients, Paraffin wax, a by-product of petroleum production is clearly not natural.
Beeswax, soy, other vegetable based waxes and perhaps bayberry are the waxes of choice by those who are environmentally conscious and by those involved in aromatherapy. Those wishing to produce natural candles face several challenges because of pros and cons of each wax and the higher cost of each wax. Soy, for instance is a soft wax. Aside from small votives and tea lights, larger soy based candles are usually available only as larger container candles. Beeswax is a much firmer wax, but is expensive and has its very distinctive but pleasant honey-like aroma and color.